Immune function effects

Administering IVFE over 12 to 24 hours in adults and 20 to 24 hours (0.15 g/kg/hour) in neonates appears to be the best strategy for promoting IVFE clearance and minimizing negative immune function effects. 

A mode by which cannabinoids may exert their multiplicity of effects may be through the modulation of the expression of chemokines and cytokines which cross-signal among immune cells and play a critical role in pro-inflammatory versus anti-inflammatory activities. Blanchard et al. (1986) and Cabral et al. (1986a) reported that induction of IFN-a/ was suppressed by chronic treatment of mice with THC. Watzl et al. (1991) indicated that cytokine activity also was modulated in human peripheral blood mononuclear cell cultures by THC. However, the non-psychoactive CBD also modulated cytokine production and/or secretion, suggesting that a non-cannabinoid receptor-mediated mode of action could also be involved. The investigators indicated that a possible explanation for the capacity of cannabinoids to act through cannabinoid receptors so as to exert a broad spectrum of immune function effects was that exposure to these compounds resulted in the expression of a differential profile of cytokines. 

Eskew ML, Zarkower A, Scheuchenzuber WJ, Graham JA. Effects of fly ash inhalation on murine immune function effect on systemic responses. Environ Res 1982 28 375-385. 

One component of the age-ielated decline in immune function is decreased production of the lymphokine that promotes the growth of T-ceUs, interleukin 2 (IL-2). Administration of recombinant-derived IL-2, both in vitro and in vivo, appears to restore certain immune functions in aged mice. Recovery of T-regulatory effects on B-ceU differentiation has been reported in human cells from elderly patients treated with IL-1 and/or IL-2 (42). Similar effects have been observed in the presence of the pentapeptide thymopentin [69558-55-0] (Arg Lys Asp Val Tyr), a weU-known IL-2 inducer. Recombinant IL-2 adrninistered to aged mice for three weeks has been shown to correct the T-ceU functional deficiency associated with antigen-specific immunoglobulin production by certain lymphoid tissue (43). 

Biochemical Functions. Ascorbic acid has various biochemical functions, involving, for example, coUagen synthesis, immune function, dmg metabohsm, folate metaboHsm, cholesterol cataboHsm, iron metaboHsm, and carnitine biosynthesis. Clear-cut evidence for its biochemical role is available only with respect to coUagen biosynthesis (hydroxylation of prolin and lysine). In addition, ascorbic acid can act as a reducing agent and as an effective antioxidant. Ascorbic acid also interferes with nitrosamine formation by reacting direcdy with nitrites, and consequently may potentially reduce cancer risk. 

To study the effect of an increased gene dosage of GR, Reichardt et al. (2000) and van den Brandt et al. (2007) generated rodent models of GR overexpression. These approaches confirmed that GR controls neuronal and immune functions in a dosage-dependent manner. These results highlight the importance of tight control of GR expression in target tissues and may explain... 

Also, chronic-duration studies have not generally shown adverse effects on organs of the immune system. Routine gross and histopathologic examination of the lymph nodes and thymus of rats, mice, and dogs exposed to endosulfan for 2 years at doses of up to 2.9 mg/kg/day (Hoechst 1989a), 2.51 mg/kg/day (Hoechst 1988b), and 1 mg/kg/day (EMC 1967), respectively, revealed no adverse effects. However, these studies did not assess immune function directly. 

Since the limited information available on the effects of dermally administered endosulfan suggests that this chemical behaves similarly across both routes of exposure and that adverse effects on immune function end points have also been observed in vitro, there is no reason to suspect that the immunotoxic effects observed following oral exposure are route-specific. Tests of immunologic function in exposed human populations would provide information as to whether immunosuppression also occurs in humans... 

Kenow, K.P., Grasman, K.A., and Hines, R.K. et al. (2007). Effects of methylmercury exposure on the immune function of common loons. Environmental Toxicology and Chemistry 26, 1460-1469. 

Since initial studies identified opioid receptors on T-lymphocytes (Wybran et al. 1979), the effects of opioids on immune function have been extensively studied. Details of these studies have been exhaustively reviewed (Madden et al. 1991 Adler et al. 1993 Peterson et al. 1998 Donahoe and Vlahov 1998 Roy et al. 2006), and will only be briefly mentioned here. In general, opioids suppress immune function. Peripheral leukocytes, including lymphocytes and peripheral blood mononuclear cells (PBMCs) can express the four major opioid receptor types, MOP, DOP, KOP,... 

The above scientific information on rice bran phytochemicals indicates that a multitude of mechanisms are operating at the cellular level to bring about specific health effects. Several health benefits of rice bran appear to be the result of the synergistic function of the many phytochemicals, antioxidants, vitamins and minerals which operates through a specific immune response. Their role in the biochemical mechanisms at the cellular level which result in major health effects is shown in Fig. 17.1. A short overview summarizing the effect of the various phytochemicals on major health issues such as cancer, immune function, cardiovascular disease, diabetes, altered liver function and gastrointestinal and colon disease will be given below. 

The sterols and sterolins in rice bran are potent immunomodulators. The best response was obtained with a 100 1 sterol/sterolin mixture that demonstrated T-cell proliferation from 20% to 920% and active cell antigens after four weeks in human subjects (Bouic et al, 1996). Another in vitro experimental study with sterol/sterolins, demonstrated a significant increase in cytokinines, interleukin-2 and y-interferon between 17% and 41 % in addition to an increase in natural killer cell activity. These experiments (Bouic et al, 1996) prove that sterol/sterolins are potent immunomodulators with important implications for the treatment of immune dysfunction. Rice bran products are excellent dietary supplements for the improvement of immune function. It is probable that the effects of rice bran on diabetes, CVD and cancer all result from improved immune function. 

Routine antioxidant vitamin supplementation, e.g. with vitamins C and/or E, of the diabetic diet should be considered. Vitamin C depletion is present in all diabetics irrespective of the presence of vascular disease. A recent study demonstrated no significant difference between the dietary intake of vitamin C (the main determinant of plasma ascorbate) in patients with diabetes and age-matched controls, confirming the view that ascorbate depletion is secondary to the diabetic process and su esting that diabetic patients require additional intakes of the vitamin to maintain optimal levels (Sinclair et /., 1994). Antioxidant supplementation may have additive beneficial effects on a wide variety of processes involved in diabetic vascular damage including blood pressure, immune function, inflammatory reactions. 

O The treatment goals for HIV infection are to maximally and durably suppress HIV replication, avoid the development of drug resistance, restore and preserve immune function, prevent opportunistic infections, and minimize adverse effects. 

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